Antioxidant supplementation and premature rupture of the membranes: a planned secondary analysis.
OBJECTIVE
The purpose of this study was to determine if antioxidant supplementation during pregnancy reduces the incidence of premature rupture of the membranes (PROM).


METHODS
A placebo-controlled, double-blind trial was conducted. PROM and preterm PROM (PPROM) were planned secondary outcomes of the trial. Women between 12(0/7) and 19(6/7) weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomized to daily treatment with both vitamin C (1000 mg) and E (400 IU) or placebo.


RESULTS
Outcome data for PROM were available for 697 of 739 patients. The rates of PROM (37/349 [10.6%] vs 19/348 [5.5%]; adjusted risk ratio [RR] 1.89 [95.42% CI, 1.11-3.23]; P = .015), and PPROM (16/349 [4.6%] vs 6/348 [1.7%]; RR 2.68 [1.07-6.71]; P = .025) were increased in the antioxidant group.


CONCLUSIONS
Contrary to expectations, vitamins C and E supplementation in this dose combination may be associated with an increased risk of PROM and PPROM.
Spinnato
Joseph A
JA
University of Cincinnati College of Medicine, Cincinnati, OH, USA.
Freire
Salvio
S
Pinto e Silva
Joao Luiz
JL
Rudge
Marilza Vieira Cunha
MV
Martins-Costa
Sérgio
S
Koch
Matthew A
MA
Goco
Norman
N
Santos
Cleide de Barros
Cde B
Cecatti
Jose Guilherme
JG
Costa
Roberto
R
Ramos
José Geraldo
JG
Moss
Nancy
N
Sibai
Baha M
BM
D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage*; D019587:Dietary Supplements; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D014810:Vitamin E / Q000008:administration & dosage*
D000975:Antioxidants; D014810:Vitamin E; D001205:Ascorbic Acid